What changes on UK hills this winter, and why it starts before the first snow

Winter on the UK hills starts before the first snow, because the light goes first. Fort William has twelve hours of daylight today and will have under seven by 21 December, and when the clocks go back on Sunday 25 October, sunset jumps an hour earlier overnight. Once there is snow and ice on top, the high summits need an ice axe, crampons and the skill to use them, and in Scotland the avalanche forecast becomes part of the plan from mid-December.

The light runs out before the snow arrives

Between now and the shortest day, the big UK hill areas lose between four and a half and five and a half hours of daylight. We calculated sunrise and sunset for Fort William, Keswick and Llanberis using the standard NOAA solar method, which is accurate to within a few minutes at sea level. On a mountain you get a little more light on the tops and a little less in deep valleys, but the trend is what matters.

Sunrise to sunset, local time. Our calculation; allow a few minutes either way.

The clock change is the moment that catches people out. On Saturday 24 October the sun sets at Fort William at about 17:56. On Sunday it sets at 16:54. Nothing about the mountain has changed, but a walk you finished in daylight last weekend now ends in the dark.

Plan the day backwards from sunset

Work out when you must be off the hill, then when you must turn round, and only then when to start. Ben Nevis is the clearest example. Most people need six to nine hours for the round trip, as we set out in how long Ben Nevis really takes. On 21 December Fort William has about six and three-quarter hours between sunrise and sunset. A slower party that starts at first light will finish in the dark, and snow on the path makes every one of those hours longer.

So set a turnaround time before you leave the car park and keep to it, whether you are at the summit or not. Carry a head torch with fresh batteries even on a short walk, because a twisted ankle at 15:00 in December becomes a descent in the dark. And leave your route and return time with someone at home.

Snow and ice change what the hill asks of you

Once there is snow and ice on the tops, the easy summer paths become mountaineering routes. Eryri National Park Authority, which manages Yr Wyddfa, puts it plainly: in winter conditions the summit cannot be reached without specialist equipment such as crampons and an ice axe, and the knowledge of how to use them. About 600,000 people climb Yr Wyddfa every year. The path you walked in July is not the same path in January.

Two points are worth taking on board before you buy anything. Crampons and an axe are no help to someone who has never used them, and can be a danger. In our view the best winter purchase is a winter skills course, and the kit can be hired for a first season. And snow on the tops does not always show from the valley, which is why the park authority publishes a daily ground conditions report for Yr Wyddfa through the winter. Read it on the morning you go.

In Scotland, the avalanche forecast is part of the plan

Scotland has real avalanches, and a dedicated forecasting service to warn about them. The Scottish Avalanche Information Service recorded 321 avalanches last season. It will run its full daily forecast across all six of its areas (Lochaber, Glencoe, Creag Meagaidh, the Northern and Southern Cairngorms, and Torridon) from Thursday 17 December 2026. If winter comes early, forecasts for some areas may start sooner.

Mountaineering Scotland’s advice is to consult the avalanche forecast every time you go into the Scottish mountains in winter, and to read the forecasters’ daily blogs, which include photographs of conditions. If you have never done it, the free Be Avalanche Aware e-learning course, from the Snow and Avalanche Foundation of Scotland, is the place to start.

What to carry on a winter hill day

Carry enough to stop and stay warm for an hour if something goes wrong, and a way to see and navigate in the dark. This is the list we would give a friend going up a UK hill between November and March:

• A head torch, with spare batteries, on every walk.
• A map and compass you know how to use. Phones die fast in the cold; keep yours warm and charged, and carry a small power bank.
• A warm insulated jacket for stops, on top of waterproof jacket and trousers.
• Hat, two pairs of gloves and a buff. Wet gloves are useless, so carry a dry spare pair.
• Stiff boots that will take crampons, if you are going high in snow.
• Ice axe and crampons for snow and ice on the tops, and only once you have learned to use them.
• A group shelter and a hot drink in a flask.

The autumn and winter risks that matter in the United States, from hypothermia above freezing to the shorter evenings, are covered in the four risks of autumn hiking. Many of them apply here too.

The verdict

Winter is the best season on the UK hills for people who plan for it, and a dangerous one for people who walk as if it were still summer. The clear, cold days after a snowfall are some of the finest in British hillwalking. Set your turnaround time by the sunset, read the mountain forecast and, in Scotland, the avalanche forecast, and learn to use an axe and crampons before you need them.

If your winter walking is really training for something bigger, the Himalaya is the obvious next step, and the autumn months there are the clearest of the year. Our comparison of trekking in Nepal and in Scotland shows how the two differ.

Keep reading

Sources: Scottish Avalanche Information Service; Mountaineering Scotland; Eryri National Park Authority; sunrise and sunset calculated with the NOAA solar position method.